Title (de)

Title (fr)

Publication

Application

Priority

DE 19734713 A 19970811

EP 9804916 W 19980806

Abstract (en)

[origin: US6373427B1] The invention relates to a radar distance measuring device. An especially linear frequency-modulated high frequency signal is emitted via an antenna and mixed with an echo signal reflected by a target object whose distance is to be determined. The distance of said target object can then be calculated by analyzing the frequency of the mix result. The aim of the invention is to improve the distance resolution or increase the accuracy of measurement. To this end, a first frequency analysis is first carried out to obtain a rough analysis result. Said rough analysis result is used to control a filtering device which then restricts the mix result in its time range to a segment around the frequency of the target object. A discrete Fourier transformation is then carried out for this segment in order to produce an analysis result with a more refined scanning step than the first frequency analysis. The measuring result is further refined, preferably by taking into account not only the frequency of the mix result as determined by the target object but also the phase relation of the oscillation of this frequency and by supplementing the measuring result with a corresponding wavelength fractional part.